switching between 2 amps, one with effects loop

[JohnForeman]

Hi all.
here it is, i have a peavey ac30 that has an effects loop that i run a few pedals through.  I also have a vox that does not have an effects loop.  i have an AB switch to change between the 2 amps.  what i want is an AB box that when i switch out of the peavey, that the pedals that are in it's effects loop will switch out of the effects loop, into the main pedal loop so those effects will be active for the VOX.  Make sense?  And can it be done with a single switch pedal?

[mth5044]

Off the top of my head, you could use a 4PDT switch to do this; however, this way does not include an LED to indicate what position the switch is in.

In this layout, you have a bunch of jacks and a ton of cables, but I guess that's something you have to be ok with. The box has an input and two outputs for each amp. It also has an internal effects loop for all your effects. Finally, it has jacks for the send and return of the effects loop on the Peavey.

In the Vox position, the input is sent to the internal effects loop, going through all your effects, then into the Vox. The Peavey input is grounded. In the other position, the input is directed straight to the Peavey input, then the internal effects loop is set up to connect to the Peavey effects loop. The Vox input is grounded.

[JohnForeman]

that looks promising.  later today i'll see if i can draw it up in a full wiring diagram so i can build it.  i'll post my drawing on here to make sure i have it all correct.
the 'no LED' is not an issue.  My original AB pedal i built doesn't have one either.
thanks

[JohnForeman]

How does this look?

[mth5044]

I believe that looks correct! The only thing I'm not 100% sure on is if the Peavy effects loop is cool having it's send and return hanging open. It may be a switching jack on the amp that when nothing is plugged in the loop is bypassed, or something like that. You mention it's a Peavey AC30 - perhaps you mean classic 30? I believe the Vox would be AC30.

In any case, the Peavey classic 30 might have a switched jack effects loop, so this may not work? Hopefully someone who knows about the classic 30 can help us out. Sorry I didn't think of it before.

[JohnForeman]

duh, yes it's a classic 30.  my bad.  and to think i might be smart enough to build something..  lol
unless i'm missing something, it may not matter if the peavey has a switching jack since that amp will be out of the loop when i'm switched to the vox.  at that point, it shouldn't matter if the snd/ret is hanging open.  Unless it creates some sort of problem that may damage the amp.

[mth5044]

Hey that's a great point. That's why they pay you the big bucks. I really don't think or see how it could damage the amp. I've heard people jumper the effects loop to add 'claritiy' or something like that. In any case, you can plug cable into the send and return without connecting them (so two cables) and see if the amp still works. Either way, you're right, I don't think it will matter.

I have a classic 30 to try it on, but where is the fun in blowing up my amp when someone else can blow up theirs? Just kidding, I think it's fine.

[wavley]

Hey that's a great point. That's why they pay you the big bucks. I really don't think or see how it could damage the amp. I've heard people jumper the effects loop to add 'claritiy' or something like that. In any case, you can plug cable into the send and return without connecting them (so two cables) and see if the amp still works. Either way, you're right, I don't think it will matter.

I have a classic 30 to try it on, but where is the fun in blowing up my amp when someone else can blow up theirs? Just kidding, I think it's fine.

That "clarity" they're getting is not running through dirty switching jacks, if you never use them they don't clean themselves and go intermittent.  When I was an amp tech years ago the first thing we did when the complaint was "cutting out" was plug a patch cable into the loop and see if it goes away, there were a good number of times that it solved the problem.  Clean the jacks, replace them, or leave a cable in depending on what the customer wanted to spend.

[harmless]

Are there any noise or ground loop implications for chaining all the grounds together like that?

I've been thinking about simple order switcher boxes (something to let me pull stuff in and out of the super ego's effects loop) and wondered if I needed to be switching both signal and ground (making things indistinguishable from wires) or if sharing the grounds was ok.